[8.x](backport #4389) Update links to search connectors docs

[mergify]

👋 These search connectors docs have moved to the Elasticsearch guide in 8.16.0, so updating those links.

ℹ️ Managed or native connectors still require the Enterprise Search server though so the link to the Enterprise Search docs for the server is still correct.

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This is an automatic backport of pull request #4389 done by Mergify.

[mergify]

Cherry-pick of 5180396 has failed:

On branch mergify/bp/8.x/pr-4389
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit 51803967.
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	both modified:   docs/en/observability/observability-ai-assistant.asciidoc

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[bmorelli25]

Not needed as the old links don't exist in this branch.

[bmorelli25]

Okay wait I just merged #4383 so now this PR is needed.

[bmorelli25]

@Mergifyio update

[mergify]

update

☑️ Nothing to do

• -conflict [📌 update requirement]
• #commits-behind > 0 [📌 update requirement]
• -closed [📌 update requirement]
• queue-position = -1 [📌 update requirement]

[mergify]

This pull request is now in conflict. Could you fix it @mergify[bot]? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b mergify/bp/8.x/pr-4389 upstream/mergify/bp/8.x/pr-4389
git merge upstream/8.x
git push upstream mergify/bp/8.x/pr-4389

[bmorelli25]

@Mergifyio rebase

[mergify]

rebase

☑️ Nothing to do

• -conflict [📌 rebase requirement]
• -closed [📌 rebase requirement]
• queue-position = -1 [📌 rebase requirement]
• any of:
  • #commits-behind > 0 [📌 rebase requirement]
  • #commits > 1 [📌 rebase requirement]
  • -linear-history [📌 rebase requirement]

[bmorelli25]

@Mergifyio update

[mergify]

update

☑️ Nothing to do

• -conflict [📌 update requirement]
• #commits-behind > 0 [📌 update requirement]
• -closed [📌 update requirement]
• queue-position = -1 [📌 update requirement]